From 1b880564cbc8da9894af065e9ac1cc9c608352a1 Mon Sep 17 00:00:00 2001
From: LillyJadeKatrin <lilly.kitty.1988@gmail.com>
Date: Sat, 15 Apr 2023 12:28:58 -0400
Subject: [PATCH] Added MemoryPeeker to AchievementManager

MemoryPeeker is a function passed by pointer into rcheevos DoFrame functionality that forms the lynchpin of the rcheevos runtime - it provides the interface by which rcheevos accesses memory and determines if the fields provided by achievement, leaderboard, and rich presence definitions are meeting the criteria needed.
---
 Source/Core/Core/AchievementManager.cpp | 34 ++++++++++++++++++++++++-
 Source/Core/Core/AchievementManager.h   |  7 +++++
 2 files changed, 40 insertions(+), 1 deletion(-)

diff --git a/Source/Core/Core/AchievementManager.cpp b/Source/Core/Core/AchievementManager.cpp
index 536f5fe63f..2d4fce9af8 100644
--- a/Source/Core/Core/AchievementManager.cpp
+++ b/Source/Core/Core/AchievementManager.cpp
@@ -9,8 +9,10 @@
 
 #include "Common/HttpRequest.h"
 #include "Common/WorkQueueThread.h"
-#include "Config/AchievementSettings.h"
+#include "Core/Config/AchievementSettings.h"
 #include "Core/Core.h"
+#include "Core/PowerPC/MMU.h"
+#include "Core/System.h"
 #include "DiscIO/Volume.h"
 
 static constexpr bool hardcore_mode_enabled = false;
@@ -62,6 +64,7 @@ void AchievementManager::LoadGameByFilenameAsync(const std::string& iso_path,
     callback(AchievementManager::ResponseType::MANAGER_NOT_INITIALIZED);
     return;
   }
+  m_system = &Core::System::GetInstance();
   struct FilereaderState
   {
     int64_t position = 0;
@@ -202,6 +205,34 @@ void AchievementManager::ActivateDeactivateRichPresence()
       nullptr, 0);
 }
 
+u32 AchievementManager::MemoryPeeker(u32 address, u32 num_bytes, void* ud)
+{
+  if (!m_system)
+    return 0u;
+  Core::CPUThreadGuard threadguard(*m_system);
+  switch (num_bytes)
+  {
+  case 1:
+    return m_system->GetMMU()
+        .HostTryReadU8(threadguard, address)
+        .value_or(PowerPC::ReadResult<u8>(false, 0u))
+        .value;
+  case 2:
+    return m_system->GetMMU()
+        .HostTryReadU16(threadguard, address)
+        .value_or(PowerPC::ReadResult<u16>(false, 0u))
+        .value;
+  case 4:
+    return m_system->GetMMU()
+        .HostTryReadU32(threadguard, address)
+        .value_or(PowerPC::ReadResult<u32>(false, 0u))
+        .value;
+  default:
+    ASSERT(false);
+    return 0u;
+  }
+}
+
 void AchievementManager::AchievementEventHandler(const rc_runtime_event_t* runtime_event)
 {
   switch (runtime_event->type)
@@ -221,6 +252,7 @@ void AchievementManager::CloseGame()
   m_game_id = 0;
   m_queue.Cancel();
   m_unlock_map.clear();
+  m_system = nullptr;
   ActivateDeactivateAchievements();
   ActivateDeactivateLeaderboards();
   ActivateDeactivateRichPresence();
diff --git a/Source/Core/Core/AchievementManager.h b/Source/Core/Core/AchievementManager.h
index 293ac00202..d041259c1c 100644
--- a/Source/Core/Core/AchievementManager.h
+++ b/Source/Core/Core/AchievementManager.h
@@ -22,6 +22,11 @@ using AchievementId = u32;
 constexpr size_t RP_SIZE = 256;
 using RichPresence = std::array<char, RP_SIZE>;
 
+namespace Core
+{
+class System;
+}
+
 class AchievementManager
 {
 public:
@@ -48,6 +53,7 @@ public:
   void ActivateDeactivateLeaderboards();
   void ActivateDeactivateRichPresence();
 
+  u32 MemoryPeeker(u32 address, u32 num_bytes, void* ud);
   void AchievementEventHandler(const rc_runtime_event_t* runtime_event);
 
   void CloseGame();
@@ -80,6 +86,7 @@ private:
                        const std::function<int(RcResponse*, const char*)>& process_response);
 
   rc_runtime_t m_runtime{};
+  Core::System* m_system{};
   bool m_is_runtime_initialized = false;
   std::array<char, HASH_LENGTH> m_game_hash{};
   u32 m_game_id = 0;